The effects of motor oil on the growth of three aquatic macrophytes

In this study, the effect of used motor oil on the growth rate of three different species of aquatic macrophytes was investigated for a three week period under laboratory conditions. Three treatments were used in pots: high oil, low oil, and a control, each with three replicate buckets (three pots per bucket). The relative growth rate (RGR) of the tested plants, Potamogeton gramineus L., Myriophyllum spicatum L., and Ceratophyllum demersum L., differed significantly between treatments (p < 0.001, one-way ANOVA). In the control treatment, C. demersum, M. spicatum and P. gramineus grew well and produced more lateral shoots than in the high and the low motor oil treatments. The longest shoot lengths were also greater for all three plants in the control than in the low and the high motor oil groups.